642544657823 has 8 divisors (see below), whose sum is σ = 646079216640. Its totient is φ = 639019513080.

The previous prime is 642544657813. The next prime is 642544657829. The reversal of 642544657823 is 328756445246.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 642544657823 - 2¹⁰ = 642544656799 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (642544657829) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2216615 + ... + 2489672.

It is an arithmetic number, because the mean of its divisors is an integer number (80759902080).

Almost surely, 2^642544657823 is an apocalyptic number.

642544657823 is a deficient number, since it is larger than the sum of its proper divisors (3534558817).

642544657823 is a wasteful number, since it uses less digits than its factorization.

642544657823 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4707037.

The product of its digits is 38707200, while the sum is 56.

The spelling of 642544657823 in words is "six hundred forty-two billion, five hundred forty-four million, six hundred fifty-seven thousand, eight hundred twenty-three".